was bogon filters, now "Brief Segue on 1918"

TJ trejrco at gmail.com
Wed Aug 6 14:35:49 CDT 2008

I think the problem is that operational reality (ease of use, visual
clarity, etc.) has long since won the war against the numerical

Things like assigning /24's per vlan make the routing table easy to read,
subnets easy to assign, etc.
	Starting from the bottom up, the next easy segregation point is /16s
per site.
	Yielding just over 250 sites, each with just over 250 network
segments, each supporting up to 250 or so users.
	Easy aggregation & summarization, easy to "own and operate" ...
grossly inefficient.  But common.

So, right or wrong is largely irrelevant - it just is.
Now go into that environment and push for a strictly-speaking efficient
allocation mechanism and let me know what kind of traction you get.

Moving forward, we can try to do things right in our IPv6 networks ...
assuming we don't inherit too much of the cruft from above.
	Use the bits to do flexible allocation while also maintaining
aggregation / summarization - it can be done.

... now let's get some work done.

>-----Original Message-----
>From: Darden, Patrick S. [mailto:darden at armc.org]
>Sent: Wednesday, August 06, 2008 1:48 PM
>To: Joel Jaeggli
>Cc: nanog at nanog.org
>Subject: RE: was bogon filters, now "Brief Segue on 1918"
>I'll reply below with //s.  My point is still: most companies do not use
>RFC1918 correctly.  Your point seemed to be that it is not a large enough
>allocation of IPs for an international enterprise of 80K souls.  My
>is: 16.5 million IPs isn't enough?
>-----Original Message-----
>From: Joel Jaeggli [mailto:joelja at bogus.com]
>Sent: Wednesday, August 06, 2008 1:31 PM
>To: Darden, Patrick S.
>Cc: nanog at nanog.org
>Subject: Re: was bogon filters, now "Brief Segue on 1918"
>That's comical thanks. come back when you've done it.
>Marshall is correct.
>If you'd like to avoid constant renumbering you need a sparser allocation
>model.  You're still going to have collisions with your suppliers and
>acquisitions and some applications (eg labs, factory automation systems
>have orders of magnitude large address space requirements than the number
>humans using them implies.
>//You used the metric of 80K people.  Now you say it is a bad metric when I
>reply using it.  Your fault, you compound it--you don't provide a better
>one.  What are we talking about then?  100 IPs per person--say each person
>has 10 PCs, 10 printers, 10 automated factory machines, 10 lab instruments,
>49 servers and the soda machine on their network?  80,000*100==8 million IP
>addresses.  That leaves you with 8.5 million....  And that includes 80,000
>networked soda machines.  I don't think you have that many soda machines.
>Even on 5 continents.  Even with your growing Asian market, your suppliers,
>and the whole marketing team.
>In practice indivudal sites might be assigned between a 22 and a 16 with
>sites with exotic requirements having multiple assignments potentially from
>different non-interconnected networks (but still with internal uniqueness
>//Err.  Doing it wrong does not justify doing it wrong.

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